From Edward Blyth 1 March 1869
7 Princess Terrace, | Regents Pk, N.W.,
March 1 /69.
My Dear Sir,
In the common Indian antelope (Antilope cervicapra and Cervicapra bezoartica) the females are usually hornless, & the males have straight and tensely spirated horns, approaching sometimes to 2 ft. in length, and of which the twist is more or less intense in different specimens. In the castrated buck, of which I have seen several, (& there is a fine one mounted as a stuffed specimen in the Calcutta museum) the horns are not spirated, but arch and gyre round to the front, with a considerable spread apart, and the colour of the coat remains permanently chestnut-brown as in the doe. In exceedingly rare instances (of which three have come to my knowledge) the doe bears horns similar to those of the castrated buck but smaller and more slender.1 Such a doe is figured as a supposed new species in one of the Indian sporting periodicals, if I mistake not in one of the latest numbers of the Bengal Sporting Magazine, New Series—
In the nilgai, also, the female is hornless, & the castrated buck develops small and slender horns, while in this instance likewise the coat remains of the same rufous-brown colour as that of the female & young, instead of assuming the colour which is styled nil (pronounced neel) or blue in the mature male.2
In the axis deer (Cervus axis)3 the mature male has a considerably darker hue than the female, which also is not assumed by the castrated buck or “[beaver]”. The African Antelope (Hippotragus) leucophaeus was long considered to be a lost species; but I believe it to be merely the mature male of what is known as the A. (H.) equinus.4 An allied species, the A. (H.) niger would appear to resemble in the difference of colouring of the sexes the Bos sondaicus, & the castrated animal would doubtless retain the colouring of the female.5 Ditto with the A. (Kobus) maria of the banks of the White Nile.6 The Indian antelope has this peculiarity (so far as I am aware) that the black colour of the buck appears & disappears according to the condition of sexual excitement, by changes of hue in the actual coat, without any renovation of the vesture—7
Yours Sincerely, E. Blyth
P.S. Only half of my article on the life of animals in wild nature appears in this week’s Land & Water. 8 On Saturday I went to Tottenham in Essex to inspect a lot of fossils & subfossils just exhumed in the course of excavations for a reservoir. The usual species, but two rather interesting human skulls. I have secured all for the Museum of the College of Surgeons.9
Sexual differences in antelopes (Indian and African).
Please cite as
Darwin Correspondence Project, “Letter no. 6638,” accessed on 3 December 2016, http://www.darwinproject.ac.uk/DCP-LETT-6638